GKM的复试acm练习2004

#include <iostream>
#include <math.h>
using namespace std;

int main()
{
	int f;
	while(cin>>f){
	if(f>=90 && f<=100)
	{cout<<"A"<<endl;}
	else if(f>=80 && f<90)
	{cout<<"B"<<endl;}
	else if(f>=70 && f<80)
	{cout<<"C"<<endl;}
	else if(f>=60 && f<70)
	{cout<<"D"<<endl;}
	else if(f>=0 && f<60)
	{cout<<"E"<<endl;}
	else
	{cout<<"Score is error!"<<endl;}
	}
	return 0;


}